Art of distilling hydrocarbon oils



Ma),Y 23, 1933. w. H. BAHLKE ART OF DISTILLING HYDROCARBON OILS Filed oct. 21, 19

Patented May 23, 1933 UNITED STATES PATENT OFFICE WILLIAM I-I. BAHLKE, OF WHITING, INDIANA, ASSIGNOR TO STANDARD OIL COMPANY, OF WRITING, INDIANA, A CORPORATION OF INDIANA ART OF DISTILLING HYDROCARBON OILS Application 1ed October 21, 1926. Serial No. 143,150.

This invention relates to the art of distilling hydrocarbon oils and particularly to the continuous distillation of such oils for separation into several finished products. 5 The invention will readily be understood from the following description of a preferred method of distilling Mid-Continent crude petroleum for the production of five finished products therefrom.

rlhe accompanying drawing illustrates diagrammatically a suitable apparatus for such distillation.

Referring to the drawing, is an oil sup.

ply pipe which leads through a series of heat l5 exchange coils 11, 12, 13, 14 and 15 and pipe 16 to a separating chamber 17, provided with a vapor outlet 18 and a liquid outlet 19 which leads Vto a coil 20 heated by a suitable furnace 21. A steam pipe 22 leads into pipe 20 19, and a pipe 23 connects the pipes 16 and 19 in parallel with the separating chamber 17, the pipes 16, 19 and 23 being provided with suitable valves so that said chamber may be by-passed if desired. The coils 11, 25 12, 13, 14 and 15 are suitably located, as will be further described, to effect a substantial preheating of the incoming crude oil. From the heated coil 20, a pipe 24 leads to an enlarged separation chamber 25, provided with a tar outlet 26 and a vapor outlet 27.

The tar outlet 26 leads to a suitable heat eX- changer 28 within which the coil 15y is located, the incoming crude oil being preheated by the outgoing tar.

The vapor outlet 27 of the chamber 25 leads into the base of a rectifying column 29, provided at its bottom with a liquid outlet 30, and at its top with a vapor outlet 31. The liquid outlet 30 of the rectifying column 29, is suitably trapped so as to constitute a liquid seal therein, thereby preventing upward passage of steam or vapors therethrough; and leads to the top of a stripping column 32. The vapor outlet 31 of the rectifying column 29, leads to the base of a rectifying column 33, provided at its bottom with a liquid outlet 34 and at its top with a vapor outlet 35. The liquid .outlet 34 of the rectifying column 33 is suitably trapped so as to constitute a liquid seal therein, thereby preventing upward passage of steam or vapors therethrough, and leads to the top of a stripping column 36. The vapor outlet 35 of the rectifying column33 leads to the base of a rectifying column 37, provided at its bottom with a liquid outlet38, and at `its top with a vapor outlet 39. The liquid outlet 38 of the rectifying column 37 is suitably trapped so as to constitute aliquid seal therein, thereby preventing upward passage of steam or vapors therethrough, and leads to the top of a stripping column 40. The vapor outlet 39 of the rectifying column 37 leads to the base of a rectifying column 41, providedy at its bottom with a liquid outlet 42 and at its top with a vapor outlet 43, which leads to a suitable condenser 44. The liquid outlet 42 of the rectifying column 41, is suitably trapped so as to constitute a liquid seal therein, thereby preventing upward passage of steam or vapors therethrough and leads to the top of a stripping column 45.

The vapor outlet 18 of the chamber 17 is l connected by valved branches 18 to the vapor inlets 27, 31, 35 and 39 of the rectifying columns 29, 33, 37 and 41, so that the vapors separated in chamber 17 may be supplied to any desired one or more of the rectifying columns.

The heat exchange coils 11, 12, 13 and 14 are located inthe upper portions of the rectifying columns 41, 37, 33 and 29 respectively thereby progressivelyl heating the incoming crude oil and effecting a partial condensation of oil vapors within the rectifying columns, thereby providing them with reflux.

The stripping column 32 is provided at its base with a pipe 46 for admission of free Steamthereinto and a liquid outlet 47 and at its top -with a vapor outlet 48 which leads to a condenser 49 which feeds into a receiver 50. The receiver 50 is providedl near its base with a valved outlet 51 which leads into the stripping column 36 near its top. At its top the receiver 50 is provided with a pipe 52, leading to a condenser 53, which feeds into a receiver 54, lprovided with a gauge glass 55 and water and oil outlets 56 and 57 near its ybottom and top` respectively,l A

gauge glass 85and Water and oiloutlets 86V condenser 64, which eeds into. areceiver 65.H

The receiver 65 is provided near its base with a valved outlet 66 which leads into the`l stripping column near its top; A t. its, top the receiver is provided with a pipe 67, leading to a condenser 68, which feeds into a receiver 69, Vprovided, with a gauge glass 70and` water and oil-outlets 71 and 72,l

near its bottom and topv respectively; A valved pipe 73 connects Withthe pipe 66y and leads to a. pump 74, the outlet 75' of which feeds into an intermediate point in the recti-y fying column 33.

The stripping column 40 is provided at-its basel With a pipe 76 for admission of free steam thereinto and a liquid outletI 77 and at its top With a vapor outlet 7 8b leading toa condenser 79, which feeds into a receiver 80: The receiver 80v is provided near its base with a valved outlet 81, which leads into the stripping column 45 near its top. At its top the receiver 8() is provided With a pipe 82 leading to a. condensery 83, which eedsinto a receiver 84, provided With a and 87, near. its bottom and topl respectively.

A. valvedlpipe 881 connects With the pipe-81 and leads to a pump 89, the outlet ofI Which feedsl into an intermediate point in;

theyrectiiying column 37. Y

` rlie stripping column 45 is provided at its base with a pipe 91 for admissionof free# steamy therei'nto and a liquid outlet 92' and at its. top W-itha vapor youtlet 93 leading to at condenser 94 Which ieedsinto a receiver 95.

The receiver.v 95 is provided near its base.

With an outlet 96 which leads-to pump 97, the loutlet 98 of Which feeds into an intermediate point in the rectifying column 41.

At its top the receiver 95 is providedy Wit-h aV pipe; 9.9leading to a condenser 100, which feeds intona receiver 101, provided with a gauge, glass 102 and Water and oil` outlets 103 and 104, near its'bottom and top respectively.

Therectifying andstripping columnsare provided internally with bubble-cap plates or other suitable-means for effecting thor ough contact treatment of ascending-vapors with descending liquids. i

The operation is as follows. Crude petroleum is pumped into pipe 10 through` coils 11, 12, 13 and-14, being thereby preheated by the vapors in rectifying columns 41:, 37,

33 and 29fand at the sameti'me eiiecti'ngr apartialcondensation of vapors-therein.H The f preheated oil proceeds .to the coil 15 in the tar heat exchanger 28 and thence through pipe 16 to a separating chamber 17, the separated gasoline or other light vapors passing off by pipe 18 and one or more of the branch pipes 18 to the rectifying column 29 or any one or more ofthe, rectifying columns. The unvaporizedoil passes to coil 20 by pipe 19, andl steam is preferably injected through pipe, 22. The separating chamber 17 may `1 be by-passed by pipey 23,' in Which case it is preferred "not to inject steam, since the light vapors exert a. similar effect of assisting volatilization of heavier hydrocarbons. The 'oilipassesitlirough.thecoil 20 and is heated therein by the furnace 21 to about 800o F. The heated oilr passes fromthe coil 20k by pipe 12.4' tol separating chamber 25 in Which al substantial proportiony of the oil sepa-rates as vapor-and passes to rectitying tower 29 by pipe 27 beingy augmented' by the vapors separated in chamber 17 and supplied to pipe 27' by; pipes 18and 18. The residue of tar which may amount'to about 5% oi the crude oil passes oil' by pipe 26 to the heat exchanger 28 in which; it' impartsv part of the heat tothe-incoming oilfpassing through coil 15.

The vapors from pipes` 27 and 18 ascendthrough the rectifyinfg'elements in column 29, being theife'by thoroughlycontacted withy the descending refluxvk condensed by the heat exchange-00H14 and, if"desired, with reflux supplied by pipe 60, and deprived of: their heaviest' constituents.` v`'The liquid from the bottom ott column 29" passes by pipe 30 to column 32v through Which it. descends in countercurrent to ascending steam: admitted by: pipe-46 and; the oil. vapors produced in..

the= column.. l* The steam passes upwardly` tlirouglrcolumn 32 effectingthe stripping of y the descending heavy oil, and finally emerges by piper 48 accompanied by vapors and f proceedsz-to.condenser'49 whichv is controlled so asto; condense practicallyallthe oil but little orn'o steam.. The condensed oil collects in receiverl `501mm which itipasses'bypipe 51 and the unc'ondensed steam is removed by pipe 52,4V which leads to condenser 53, in Which thesteam is condensed andv the Water collected in receiver 54. Any oil vapors accora-y panying the steam, are likewise condensed andthe oil, collecting in the receiver 54 can beremoved by outlet 57 vwhen desired. The oil'lpassing from receiver 50 by pipe 51 may be allowed to. pass to the top of stripping column 3.6 or may ,be pumped by pipe 58, pump V59 and pipe l60 to anV intermediate point,` ofthe rectifyingcolumn 29, to vserve as refluX therein, or a part of the oil may be passedto each column 29 and 36. The column 32.'is operated so as to yield by pipe 47, a heavy parailin distillate constituting about. 19"/70' of the original crudefo'il. y

The vaporsjfrom column 29 pass by pipev 3:1 tof the base of column 33 and ascend therethrough, being thereby thoroughly contacted with the descending reflux derived'by partial condensation of vapors by the oil passing through coil 13, and if desired, with reflux supplied by pipe 75. The refluXed oil from the base of tower 33 passes by pipe 34 to the top of column 36, being augmented, if desired, by oil from` receiver 50 which may be supplied to the column 36 by pipe 51. rlhe liquid passes downwardly through column 36 being therein subjected to the action of ascending steam admitted at the base of the tower 36 by pipe 61. After passing up through the stripping column 36, the steam and oil vapors pass by pipe 63 to condenser 64, which is controlled so as to condense practically all the oil but little or no steam. The condensed oil collects -in @receiver 65 from which it passes by pipe 66, and the uncondensed steam is removed by pipe 67, leading to lcondenser 68 in which the steam is condensed and the water collected in receiver 69. Any oil vapors accompanying the steam are likewise condensed and the oil collecting in the receiver 69, can be removed by outlet 72, when desired. The oil passing from receiver 65 by pipe 66 may be allowed to pass to the top of stripping` column 40 or may be pumped by pipe 73, pump 74, and pipe to an intermediate point of the rectifying column 33 to serve as reflux therein, or a part of the oil may be passed to each column 33 and 40. The column 36 is operated so as to yield by pipe 62, a paraffin distillate constituting about 19% of the original crude oil.

The vapors from rectifying column 33 pass by pipe 35 to the base of rectifying column 37, and ascend therethrough, being thereby thoroughly contacted with the descending reflux derived from partial condensation of vapors by the oil passing through coil 12 in the top of the column, and if desired, with reflux supplied by pipe 90. The reiiuxed oil from column 37 passes by pipe 38 to the top of the stripping column 40 being augmented, if desired, by oil from receiver 65, which may be supplied to the column 40 by pipe 66. The liquid descends through the column 40 in countercurrent to steam, admitted by pipe 76 and vapors stripped from the descending oil. After passing up through the stripping column 40, the steam and oil vapors pass by pipe 78 to condenser 79, which is controlled so as to condense practically all the oil but little or no steam. The condensed oil collects in receiver 80, from which it passes by pipe 81 and the uncondensed steam is removed by pipe 82k leading to condenser 83 in which the steam is condensed and the water collected in receiver 84. Any oil vapors accompanying the steam are likewise condensed and theoil collecting in the receiver 84 can be removed by outlet 87, when desired. The oil passingfrom receiver 80 by pipe 81 may be allowed to pass to the top of stripping column 45 or may be pumped by pipe 88, pump89and pipe 90 to an intermediate point of the rectifying column 37 to serve as reflux therein, or a part of the oil may be passed to each column 37 and 45. The column 40 is operated so as to yield by pipe 77 gas oil constituting about 15% of the original crude oil. 1

` The vapors from rectifying column 37 pass by pipe 39 to the base of rectifying column 41 and ascend therethrough, being thoroughly contacted with ythe descending reflux derived from partial condensation of vapors by the oil passing through coil 11 in the top of the column, and with reflux supplied by pipe 98. The vapors from the rectifying column 41 pass by pipe 43 to condenser 44, giving a yield of rectified gasoline amounting to about 32% of the original crude oil. The refluxed oil from column 41 passes by pipe 42 to the top of the stripping column 45, being augmented, if desired, by oil from receiver 80, which may be supplied to the column 45 by pipe 81. The liquid descends through the column 45, in countercurrent to steam admitted by pipe 91 and vapors stripped from the descending oil.

After passing through the stripipng column 45, the steam and vapors pass by pipe 93 to condenser 94, which is controlled so as to condense practically all the oil but little or no steam. The condensed oil collects in receiver 95 and is pumped therefrom by pipe 96, pump 97 and pipe 98 to an intermediate point of rectifying column 41. rlhe uncondensed steam passes from receiver 95 by pipe 99 to condenser 100 in which the steam is condensed and the water passes to receiver 101. Any oil vapors accompanying the steam are likewise condensed and the oil collecting in the receiver 101 can be removed by outlet 104, when desired. The column 45 is operated so as to yield by pipe 92 refined oil constituting about 10% of the original crude oil.

The character and yield of the fractions drawn off by pipes 47, 62, 77 and 92 from the stripping columns 32, 36, 40 and 45 can readily be controlled by regulating the amount of steam supplied thereto by pipes 46, 61, 76 and 91. The removal of water from the receivers 54, 69, 84 and 101 is controlled by the valves on pipes 56, 71, 86 and 103, the level of the water in the receivers being shown by gauge glasses 55, 70, and 102.

In order to permit oil condensed from the steam and vapors resulting from each stripping operation tobe passed to any of the columns 29, 33, 37 and 41 the following connections may be employed: A valved line 110 may lead from line 58 to line 73, a valved line 111 may lead from line 73 to line 88, and a valved line 112 may lead from line 88 to line 96. Lines 110 and 111 may be connected bymeans of a valved by-'passvline 113 andlines 111 and 112 may be connected by means of a valved by-pass line 114. By means of these connections any `portion of the oil condensate may be Withdrawn from any one of the lines 58, 78, 88 and 96 and passed to any one'or more of the said lines whereby the oil condensate may be passed to any of the rectitying columns 29, 33, 37 and 4:1. Y

It is tobe understood that While a particular treatment of Mid-Continent crude petroleumy has been described by Way of example, thelinvention is not limited thereto, since the process may he read-ilyfadapted toprovide a different range of products and may also be used for'the treatment oi other crude petroleums and other petroleum mixtures. t is further to'be understood thatthe present'invention is not intended to be limited to the apparatus or method 4oi' operation `described herein,veXcept by the terms of the appended claims.

I claim:

1. rlhe method of distilling hydrocarbon oils vvhich consistsin vaporizing'the oil, subjecting the vapors to a partial condensation, subjecting the condensate therefrom-to the stripping` action oi.v steam, withdrawing the stripped condensate, condensing oil from 'the steam and vapors from the stripping operation, and passing the oil thus condensed directly to the vapors undergoing partial condensation.

2. The method of distilling hydrocarbon oils Which consists in vaporizing the oil, subjecting the vapors to a partial condensing andrectitying operation, subjectingthe condensate therefrom to the stripping action of steam, withdrawing the stripped condensate,-condensing oil from the steam and vapors ifrom the stripping operation, and-passingr oil thus condensed directly to the vapors undergoing partial `condensation and rectification.

3. The method ot distilling hydrocarbon oils which consists in vaporizing the oil, subjectingthe vapors to two successive partial condensing and rectifying operations, subjecting the condensate from the iirstlpartial condensing' vand rectifying operation to the stripping action of steam, condensing oil from the steam and vapors from said stripping operation, passing a part-oi the condensed oil directly to the vapors in the first partial condensing and rectityingoperation, and subjecting the remainder ot said oil together lWith the'condensate `from the secondpartial condensing and rectifying operation to the stripping action ot steam.

1. The method of distilling hydrocarbon oils which consists `in vaporizing the oil, subjecting the vapors to tivo successive partial vcondensing and rectifyingoperations, subjecting the condensate from the iirst partial condensing and rectitying'operation to the stripping action of steam, condensing oil romthe steam and vapors from said stripping operation, subjecting said condensed oil `together With the condensate from `the second'partial condensing:y and rectiiying operation to the .stripping action of steam, condensing oil from the steam and vapors from the second steam stripping operation and removing steamtherefrom, and passing the condensed oil to the vapors in the second partial condensing and rectifyingoperation.

5. The method 'of'distilling'hydrocarbon oils Which comprises passing 4a coniined stream ot oil through a heating zone Vto a separating chamber, kremoving the 'vapors `from the separating chamber, subjecting said lvapors to a seriesof partial condensing and rectifying operations, subjecting the rectiiied condensate from each partial condensing and rectifying operation to afstripping operation With steam, withdrawing the stripped condensate, condensing oili'rom the steam and vapors rom'the stripping operation, and supplying oil thus condensed directly to the vapors in one 'ot said partial condensing-and rectifying operations.

6. rilhe method oi distilling hydrocarbon oils which comprises passing a confined stream of oil through a heating Zone to a separating chamber, removing the vapors from the separating chamber, subjecting said vapors to a series of partial condensing 'and rectifying operations, subjecting the rectified condensate from each of said operations to a stripping operation with steam, Withdrayvingthe stripped condensate, concondensing oil {from-the steam and vapors 't1-omi the stripping: operation, and supplying oil thus lcondensed directly to -the vapors in a subsequent one of the partial condensing and rectifying operations.

7. The method of distilling hydrocarbon oils lwhich comprises passing a coniined stream ot' oil through v'a heating zone to a separating chamber', removing the vapors from the separating chamber, subjecting said vapors to a series of partial condensing and rectifying operations, subjecting the rectified condensate from each of said operations toseparate-stripping operations With steam, withdrawing the stripped condensates, separately condensing oil from the steam and vapors from each oi the separate stripping operations, and supplying oil thus condensed directlyto the'vapors in thepan tial condensing and rectiiying iopera'tions corresponding to each ofthe said stripping operation-s.

8. Themcthod of distilling hydrocarbon oils, Which comprises passing a confined stream of oil through a heating zone to a separating chamber, removing the vapors from the separating chamber, subjecting` said vapors to a series of partial condensing and rae rectifying operations, subjecting the rectified condensate from each of said operations to separate stripping operations with steam, condensing oil from the steam and vapors from one of the stripping operations, and supplying a part of the condensed oil to the vapors in the partial condensing and rectifying operation corresponding to said stripping operation and a part to one of the subsequent stripping operations.

9. rlhe method of distilling hydrocarbons oils which comprises passing a confined stream of oil through a heating zone to a separating chamber, removing the vapors from the separating chamber, subjecting said vapors to a series of partial condensing and rectifying operations, subjecting the rectied condensate from each of said operations to separate stripping operations with steam, condensing oil from the steam and vapors from one of the stripping operations, and supplying a part of the condensed oil to the vapors in the partial condensing and rectifying operation corresponding to said stripping operation and a part to the next subsequent stripping operation.

10. The method. of distilling hydrocarbon oils which comprises passing a confined stream of oil through a heating zone to a separating chamber, removing the vapors from the separating chamber, subjecting said vapors to a series of partial condensing and rectifying operations, subjecting the rectified condensate from each of said operations to separate stripping operations with steam, condensing oil from the steam and vapors from one of the steam stripping operations directly supplying the condensed oil to the vapors in the corresponding partial condensing and rectifying operation, condensing the oil from the steam and vapors from another of the said stripping operations and supplying the same to one of the subsequent stripping operations.

ll. The method of distilling hydrocarbons oils which comprises passing a confined stream of oil through a heating zone to a separating chamber, separately removing tar and vapors from said chamber, passing said vapors through a series of rectifying columns, and condensing the final vapors therefrom, passingthe incoming oil in heat exchange relationship with the vapors in the upper portion of said columnswhereby the incoming oil is preheated and part of the vapors is condensed to form reflux for the columns, passing the incoming oil in heat exchange relationship with the tar produced whereby it is further preheated, removing rectified condensate from each rectifying column to a corresponding stripping column, subjecting the condensate in each stripping column to the action of steam and separately withdrawing the stripped liquid fractions thus produced, subjecting the steam and vapors from the stripping columns to condensation and removing steam therefrom, supplying the oil condensed from the steam and vapors from the last stripping column to the rectifying column corresponding thereto, and supplying oil condensed from the steam and vapors from the other stripping columns to the rectifying columns corresponding thereto and to the neXt subsequent stripping columns.

l2. The method of distilling hydrocarbon oils which comprises passing a confined stream of oil through a heating zone to a separating chamber, separately removing tar and vapors from said chamber, passing said vapors through a series of rectifying columns, and condensing the final vapors therefrom, passing the incoming oil in heat eX- change relationship with the vapors in the upper portion of said columns whereby the incoming oil is preheated and part of the vapors is condensed to form reflux for the columns, passing the incoming oil in heat eX- change relationship with the tar produced whereby it is further preheated, removing light vapors from the oil thus preheated and supplying same to one of said rectifying columns, supplying steam to the oil and passing it to said heating zone, removing rectified condensate from each rectifying column to a corresponding stripping column, subjecting the condensate in each stripping column to the action of steam, separately withdrawing the stripped liquid fractions thus produced, subjecting the steam and vapors from the stripping columns to condensation and removing steam therefrom, supplying the oil condensed from the steam and vapors from the last stripping column to the rectifying column corresponding thereto, and supplying oil condensed from the steam and vapors from the other stripping columns to the rectifying columns corresponding thereto and to the next subsequent stripping columns.

13. The method of distilling .hydrocarbon oils which comprises passing a confined stream of oil through a heating zone to a separating chamber, removing the vapors from the separating chamber, subjecting said vapors to a series of partial condensing and rectifying operations, subjecting the rectified condensate from each of said operations to separate stripping operations with steam, condensing oil from the steam and vapors from one of the steam stripping operations, supplying the condensed oil to the vapors in the corresponding partial condensing and rectifying operation, condensing the oil from the steam and vapors from another of the said stripping operations and supplying the same to the next subsequent stripping operation.

WILLIAM H. BAHLKE. 

